Carton



July 23, 1963 A. w. HAGAN ETAL. 3,098,600

By PAUL F. SIMPSON ATTORNEYS July 23, 1963 A. w. HAGAN ETAL 3,098,600

CARTON Filed Aug. 24. 1961 3 Sheets-Sheet 2 lll 49 INVENToRs ALERT W. HAGA/v By PAUL E SIMPSON A TTORNE YS 3,098,660 CARTGN Albert W. Hagan, Stratford, Conn., and Paul F. Simpson, Mechanicsburg, Pa., assignors to Roy S. Sanford @t Company, Gxford, Conn., a partnership Filed Aug. 24, 1961, Ser. No. 133,706 Claims. (Cl. 229-37) This invention relates to cartons .of paperboard and other sheet materials suitable for the formation of cartons having foldaxble end flaps, and particularly to a novel sift-proof construction for a carton of the above type.

`One of the objects of the present invention is to provide a novel paperboard carton blank which is readily adapted for quick and eiicient sealing, the construction being such that complete sealing .of all pin holes and cracks is achieved, thus providing a container having end portions which are completely sift-proof when the carton is utilized for finely powdered materials such as flour, tor example.

Another :object of the invention is the provision of a carton construction so constituted as to eliminate the need for innerbags or foverwraps commonly utilized for the purpose of preventing sifting of the powdered contents.

A 'further object of the invention is to provide a siftproof carton of polygonal cross-section `formed from a single piece of low cost material such as paperboard.

Still another object of the invention is to provide a onepiece carton blank scored to permit yfolding in such a mann-er as to permit efficient and positive sealing of the end flaps under relatively low pressure.

A still further object of the invention is to providea sift-proof carton of paperboard or the like, so constructed as to effectively seal the corners against leakage ofthe contents without relying on adhesive to close the pin holes which are commonly formed at the corners in cartons of this general type.

In the manufacture of paperboard cartons ot this general type, it is not too dilicult to properly seal one end of the carton, since when the iirst end is sealed, the end flaps can be held together under high pressure, a mandrel being inserted in the carton to support the llaps on one side, and a pressure plate being placed against the aps on the outside thereof in 4order to properly seal the flaps. Diliculty is experienced, however, in sealing the other end of the carton after it bas been lled, and it is further an important object of the invention to overcome this ditiiculty and to provide a construction wherein the end of the carton which is sealed after iilling of the carton can be made sift-proof with very llittle pressure being applied to the folded end aps which close the end of the carton.

A still 4further object of the invention is Ito provide a new and novel corner construction yfor a carton.

Yet another object of the invention is to provide a corner construction yfor a paperboard carton which will stand rough handling without causing the corners of the carton to leak.

Another object of the invention is a provision of a carton blank so constituted as to permit tfolding and side seaming the carton blanks to :form flat shells which may be shipped trom the canton plant to the packaging plant in a liat condition.

Still another object of the invention is the provision of a carton blank so constituted as to permit the formation of the blank into a carton tube of polygonal crosssection whereby the foldable end tlaps of the carton tube can be folded outward at substantially 90 to the corresponding sidewalls of the carton in such a manner that a coating of ,glue can be applied to the surfaces ot Patented July 23, IQSS the o-ldable end aps with conventional ,glue applying equipment.

A further object of the invention is the provision of a carton blank so constituted as to permit formation of the blank into a nished carton on equipment which is now available at packaging plants.

These and other objects and novel features of the invention will appear more fully hereinafter from the following detailed description when taken in connection with the accompanying drawings, wherein one embodiment of the invention is illustrated. It is to be expressly understood, however, that the drawings are utilized for purposes of illustration only, and are not to be taken as a denition of the limits of the invention, reference being had for this purpose to the appended claims.

In the drawings wherein similar reference characters refer tot similar parts throughout the several views:

|FIG. 1 is a plan view of a blank adapted to be formed into a carton of the above type;

FIG. 2 is a perspective view of a carton tube formed from the blank of lFIG. l;

FIG. 3 is a perspective view of a completed carton formed from the tube [of rFIG. 2;

FIG. 4 is an enlarged fragmentary perspective view of one corner of a carton during one stage of the end sealing operation;

FIG. 5 is a sectional view off the corner of FIG. 4 taken along line 5-5 of that View;

FIG. 6 is a perspective View of yone corner of a completed carton;

IFIG. 7 is a sectional View of the corner shown in FIG. 6 taken along line 7-7 lof that view, and

FIG. 8 is a perspective view of a mandrel and pressure pads which may be utilized in the formation of the carton.

The present invention is particularly directed to a carton construction which is economical in the use of paperboard, which can be readily fabricated, and which does not require complicated folding mechanism in order to produce a sift-proof carton. In this connection, it should be noted that the corners of a conventional carton of the type utilized lfor the packaging of flour, cake mixes or the like, form a very rigid structure, and that in the event the carton is dropped on the floor and hits on a corner, the carton is generally damaged at the corner to such an extent as to rupture the paperboard and cause serious sitting of the contents. In the event an overwrap is used, this is generally ruptured at the corner, and since the carton itself is not sift-proof at the corner, leakage occurs. It is well known that such cartons receive rather rough handling in chain grovery stores and the like, and consequently the loss `due to damaged cartons is quite high.

The carton of the present invention has a corner construction which overcomes these difficulties, since the corner is not rigid in the sense that the corners of a conventional carton are rigid, and While crushing of the corners of the carton made in accordance with the invention may occur due to dropping of the carton, and may change the appearance of the corner by crushing some of the paperboard, it does not cause leakage or sifting at the corners. Cartons of this construction have been dropped repeatedly trom a heightof two or three feet without causing sitting of the contents, the contents utilized i-n these tests being very finely divided our. Explaining the matter in another Way, it is pointed out that the rigid corner of the conventional carton buckles when dropped (on the licor, thus rupturing the paperboard. The carton of the present invention is so constructed that the corners are buckled during manufacture of the carton so that further displacement can spaanse occur during rough handling of the carton without rupturing the paperboard.

Much of the carton machinery now in use as packaging plants is -so constituted as to require that the foldable end lflaps on the carton be folded outward at substantially 90 to the sidewalls lof the carton in order to permit glue to be applied to the surface of the flaps, and the construction set forth herein which permits such folding is particularly advantageous in this respect since conventional gluing machinery can be used for this purpose. As heretofore indicated, the construction is also such as to permit the carton blanks to be folded and side seamed 'on machinery at the carton plant for shipment in a ilat condition to the packaging plant, a procedure which is preferred by both the carton manufacturer and the packaging plant in many instances.

Referring more particularly to FIG. l, the present invention is illustrated therein as including a container blank 4, shown for convenience in description in a vertical position, and having adjoining vertical main sidewall panels 5, .6, 7 and 8, and a vertical glue flap panel 9 adjoining the right side of the panel 8. At the upper end of the blank, there are corresponding foldable end llaps itl, lll, 12, 13 and 14, the bottom end of the blank being provided with corresponding foldable end flaps 15, lo, 17, i3 and 19. The foldable end flaps lo and 12 and 15 and 17 are preferably much shorter than the width of wa-ll panels and 8. The flaps llltl and 12 and 15 and 17 are minory flaps, and the others are major aps, the latter having a length equal tothe width of the sidewall panels and 7. The upper foldable end aps are separated as `shown by cut lines 2G, 21, 22 and 23, while the lower foldable end aps are separated by cut lines 24, 25, 26 and 27. In order to permit folding of ythe blank to provide a shell or carton tube, the junction of the vertical panels is defined by vertical score lines 28, 29, 3o and 3l. When the blank is later folded, the surface shown in FIG. l is on the inside of the carton.

The junction of the sidewall panels with the upper foldable end flaps is defined by a horizontal score line 32, whiie the junction fof the sidewall panels a-nd the corresponding end flaps at the lower end of the blank is defined by a horizontal score line 33. Although the score lines between the sidewall panels are referred to as vertical lines, and the score lines at the junction of the sidewall panels and foldable end flaps are referred to as horizontal score lines, it is understood that these terms are used for convenience and clarity of description only, and that the carton lblank may be otherwise oriented.

As shown in the drawing, the cut lines separating the foldable end flaps extend from the outer edges of these flaps to the horizontal score line 32 at the upper end of the 'blank and to the horizontal score line 33 at the lower end of the blank, and that the vertical score `lines between the sidewall panels preferably extend to the horizontal score lines at either end. The sidewall panels and glue ap panel are provided as shown with diverging score lines 34 and 35, these intersecting as shown on the vertical score lines 28, 29, 30, and 31 and diverging therefrom, and preferably diverging at an obtuse included angle to intersect the adjacent horizontal score lines on the blank, the score lines 34 and 35 preferably being of equal length. The foldable end flaps are provided with converging score lines 36 and 37, the score lines 36 preferably being at an angle of 45 to the horizontal score line 32 and extending from the junction of the score lines 34 with the horizontal score line to the cut lines 20, 21, 22 and 23 respectively. In like manner, the score lines 37 are at an angle of 45 to the horizontal score line 32, and extend from the intersection of the score lines 35 with the horizontal score line to the above cut lines. The score lines 36 and 37 form triangular panels 36a and 37a at the inner ends of the flaps. In addition to the foregoing, a triangular notch 38 is provided on the left edge of the wall panel 5 at either l end, one side of the notch on the wall panel beingl defined by a rcut line 39, this cut line having substantially the same length as the score lines 35, and having the same angle with respect to the horizontal score line 32. The other side of the notch is in alignment with the score lines 32 or 33 as the case may be. In addition to the foregoing, a score line 4) is provided on the lower left hand corner of the foldable end flap l@ and the upper left hand corner of Hap l5, these score lines intersecting the horizontal score lines at the intersection of cut lines 39 with the horizontal score lines iand extending to the left edge of the end ap at Ian angle of 45 to the horizontal score lines.

The score lines 34, 35, 36, 37 and il at the lower end of the blank are preferably arranged in the same manner as those at the upper end of the blank. Also, the major end flaps 11 and 13 and 16 and 18 are provided at their outer corners with 45 sco-re lines el, 42, a3, 44, (i5, 46, 47 and 48 as shown, these lines having the same length as the score lines 36 and 37. lt should also be noted that on the glue flap panel, the horizontal score lines 32 and 33 are extended to the right thereon beyond the intersection of the score lines 35 and 37 with the horizontal score lines. The lscore lines 40, 4l, 42, e3, 44, 45, lio, i7 and 43 form triangular panels 4tlg, da, 42a, 43a, dem, 45a, 46a, 47a, and 43a at the corners of the end flaps.

Although, as heretofore stated, the blank is shown with the vertical score lines extending from one horizontal score line to the other, it is pointed out that in certain instances it may be desirable to terminate these score lines at either end at the junction of the score lines 34 and 35. The arrangement shown, however, is the preferred form of the invention. Although the angles of the score lines 34 and 35 is not critical, cartons were made wherein these lines had'an angle of approximately 31 to the horizontal score line, making the obtuse included angle between the two score lines 118. Utilizing these angles, the distance between the junction of score lines 34 and 36 on the one hand and score lines 35 and 37 on the other hand was :approximately .625". These dimensions and angles are not critical, however, and may be varied over la considerable range, depending to some extent on the thickness of the paperboard and the character of the material utilized. The finished appearance desired in the container also affects the angles utilized and the variation from the .625" dimension which is desirable. In any case, however, it is pointed ltout that these angles and the dimension given are not to lbe considered as limiting of the invent-ion. In addition, although the divergmg and converging score lines, as well as the 45 score lines at the outer ends of the major aps are shown as being straight lines, these lines can be curved slightly if desi-red.

When the carton blank is folded to forrn a flat shell, and subsequently -a completed carton, it will be under- Istood that in forming the shell, the panel S will be folded about the vertical score line 30, and panel 5 will be folded about the vertical score line 28 with the inner surface yat the edge of the panel 5 and at the edges of the foldable end flaps 10 and 15 respectively over-lapping the outer surfaces of the glue flap panel 9 and the corresponding end flaps 14 and i9 and being adhesively secured thereto. This may be done on conventional machines available in present canton plants and the shell is then ready to ship in a llat condition to the packaging plant. When this is done, the edge 39 of the notch 38 substantially ycoincides with the score line 35 on the glue flap 9, while the other edge of the notch coincides with the horizontal score line 32 on the glue ap panel. In like manner, the 45 score line 49 on the ap 16` will substantially coincide with the 45 score line 37 on the foldable end flap 14, the same being true at the lower end of the carton if this end is made in the same manner as the upper end.

Following the formation of the flat shell, the shell is opened up to form a tube of rectangular cross-section as shown in FIG. 2, and is placed on a mandrel `49, shown in FIG. 8. The mandrel is provided on opposite sides thereof with the carton supports 5i? and 51 which can grip the sides of the carton for purposes to be described hereinafter, and dur-ing the closing of the rst end of the carton, these may be removed, and the carton so placed on the mandrel as to have the horizontal score line substantially coincide 'with edge 52 at the upper end of the mandrel. The end flaps at one end of the carton are then folded over in overlapping relationship and adhesively secured together by placing a pressure block 53 against the outer end ap, any suitable type of adhesive being used for this operation. In the preferred form of the invention, the flaps and 'l2 are first folded inwardly onto the mandrel, and thereafter the flaps 1l and 13 are folded over these flaps. The lengths of the end flaps are so chosen that at least three of the end flaps overlap directly at the apex of each corner of the carton, and this condition is met if the major flaps are the same length as the width of sidewalls 5 and 7.

At the end of the above operation, the corner construction is the same as that of a conventional carton, and reference is had to FIGS. 4, 5, 6 and 7 in connection with the further operations which take place in forming the carton corner in accordance with the principles of the invention, it being noted that the corner shown in the above views is the corner at the junction of the upper ends of wall panels 7 and 8. The corner now appears as shown in FIGS. 4 and 5, the three end flaps 13, 11 and l2 being in overlapping relationship at the apex of the corner as shown with the 45 score lines 37, 42 and 36- and the corresponding triangular panels 37a, 42a and 36a being substantially in register one above the other and dening a triangular corner portion 54 at the upper end of the carton which is later depressed to form the sift-proof corner with the end flaps 13, lll and 12 overlapping substantially at the apex of the carton corner. It will be noted that the score lines 34 and 3S on the blank form sides of small triangular portions 55 and 56 on the walls of the blank, and these are shown in FIG. 4 at this stage of the carton formation.

In order to complete the formation of the corners, the carton isthen placed on mandrel 49 with the supports 5@ and 51 being secu-red to the mandrel in such a manner as to support the carton thereon with the horizontal score line a short distance above upper edge 52 of the mandrel. A second pressure plate 57' provided at each corner with wedge-shaped members 5S, as shown in FIG. 8, is placed over the end of the carton and pressed downward, the

members 5S serving to push the triangular corner portions S4 of the carton end down about the 45 score lines to the approximate position shown in FIGS. 6 and 7. When this occurs the triangular panels 55 and 56 tend to buckle inwardly along score lines 34 and 35, these panels buckling to form adjacent generally triangular panels 59 and 6i) and 6-1 and 62 respectively, the panels 59 and 60 folding inwardly in generally overlapping relationship and the panels 6l and 62 folding in like manner. This action causes the paperboard material to be crowded into the corners to effectively seal the pin holes, the depressed corner portions 54 remaining depressed slightly below the plane of the major portion of the end ap 13 when the carton end is completed. In the event the minor end aps l@ and l2 and 15 and 17 are of the same length as the width of the sidewalls 6 and 8, the outer corners of these flaps are also provided with 45 score lines.

The carton is then filled, and the end flaps at the other end of the carton are then folded over each other in like manner, pressed together with adhesive therebetween by pressure plate 53, after `which the corner portions 54 are depressed by the operation of the pressure plate 57 and the projections S8 thereon. When the end aps are pressed together by the pressure plate 53, the sidewalls are strong enough to permit sealing of the end aps along their edges, the corners being sealed as heretofore described. It should be pointed out that during the corner depressing s operation, the notches 38 insure that during depression of the corner adjacent the side seam or glue ilap, it is only necessary to buckle one layer of paperboard at each end of the blank, this layer being the triangular portion 56.

From the foregoing, it will be apparent that the carton of the invention can be made on conventional machines with very little modiication, can be side seamed on available gluing equipment, can be shipped either as a blank or as a flat side seamed shell, and that the end flaps can be folded outward from the walls Ifor the application of glue without rupturing the paperboard, since the cut lines between the end flaps extend to the horizontal score lines 32 and 33.

While the invention has been illustrated and described with considerable particularity, it will be understood by those skilled in the art that various changes may be made without departing from the spirit of the invention. Reference will therefore be had to the appended claims for a .definition of the invention.

What is claimed is:

1. A one-piece blank Ifor a sift-proof carton of rectangular cross section formed of sheet material, said blank including four vertical sidewall panels joined along vertical score lines, a foldable end ap at the end of each sidewall panel, the end flaps being jointed -to the sidewall panels -along a horizontal score line and the two end aps at the ends of two alternate sidewall panels having substantially the same length as the width of each of the other two wall panels, cut lines separating said end flaps and terminating substantially at said horizontal score line, diverging score lines on each adjacent pair of wall panels extending from a point on the vertical score line therebetween to the horizontal score line on either side of said vertical score line, converging score lines on the end` iaps at t-he ends of said adjacent wall panels extending from the junctions of the diverg-ing score lines with the horizontal score line to the cut line between said last named end flaps and being at an angle of 45 to the horizontal score, line, and diagonal score lines at the outer corners of each of said two end flaps extending from the cut lines at the edges of the flaps to the ends of the flaps at an angle of 45 to the cut lines, said diagonal score lines havin-g substantially the same length as said converging score lines.

2. A one-piece blank for a sift-proof carton as set forth in claim l, wherein the included angle between said diverging score lines is an obtuse angle.

3. A one-piece blank for a sift-proof container of rectangular cross section formed of sheet material, said blank including four vertical sidewall panels joined along vertical score lines and a Vertical glue ap panel joined to the outer sidewall panel on one side of the blank along a vertical score line, foldable end flaps at the ends of the sidewall panels and glue flap panel joined to the corresponding wall panels and Iglue ap panel along a horizon tal score line and separated by cut lines terminating at the horizontal score line, the end flaps at the ends of two alternate sidewall panels having substantially the same length as the width of each of the other two sidewall panels, diverging score lines on each pair of adjacent vertical panels extending from a common point on the vertical score line between the panels to the horizontal score line, converging score lines on the end -aps at the ends of said adjacent wall panels extending from the junctions of said diverging score lines with the horizontal score line to the cut ilines between said end aps at an angle of 45 to the horizontal score line, diagonal score lines at the `outer corners of the two end aps at the ends of said two alternate w-all panels, said last named score lines extending from the cut lines at the edges of said two end flaps to the ends thereof at an angle of 45 to the cut line and having substantially the same lengths as said converging score lines, and a triangular shaped notch cut in tthe edge of the other outer sidewall panel on the other side of said blank, one side of said notch coinciding with said horizontal score line and the other side extending from said horizontal score line to the edge of said other outer sidewall panel, said other side of the notch being defined by a cut line of substantially the same length as said diverging score lines and having substantially the same angle to the horizontal score line as said diverging score lines.

4. A sift-proof corner construction for a carton of rectangular cross section formed from a onepiece blank of sheet material and having four sidewall panels disposed at right angles to each other and end aps at the ends of the sidewall panels folded in overlapping relationship Iand adhesively secured together, said corner construc tion including at lleast three superimposed triangular corner portions of three of said overlapping end flaps, said triangular portions having apices substantially at said carton corner, said three triangular portions being bodily folded inwardly with respect to the plane of said folded end aps about superimposed score lines on said three end flaps, said score lines having yan angle of 45 to the planes of adjacent sidewall panels, and two small adjacent generally triangular panels on each adjacent sidewall panel folded inwardly of the planes of the corresponding sidewall panels in generally overlapping relationship, said small triangular panels -havinlg apices at the junction `of the sidewall panels and adjacent end flaps `and positioned in line with the ends of said superimposed score lines.

5. A sift-proof carton of rectangular cross section formed from a one-piece blank of sheet material, said carton including `four sidewall panels forming a tube of rectangular cross vsection and end llaps at the ends of the sidewall panels folded in overlapping relationship and adhesively secured together, superimposed triangular portions of at least three of said end aps at each corner of the carton `being crushed bodily inwardly `of the carton end at each corner at an angle with respect to the plane of the folded end ilaps along superimposed score lines on said three end flaps, said score lines having an angle 'of 45 to the planes of adjacent sidewalls, and small adjacent triangular portions of each sidewall at each corner below and in line with said triangular portions of the end llaps folded inwardly of the planes of the correspond ing sidewall panels in generally overlapping relationship.

References Cited in the tile of this patent UNITED STATES PATENTS 

1. A ONE-PIECE BLANK FOR A SIFT-PROOF CARTON OF RECTANGULAR CROSS SECTION FORMED OF SHEET MATERIAL, SAID BLANK IN CLUDING FOUR VERTICAL SIDEWALL PANELS JOINED LONG VERTICAL SCORE LINES, A FOLDABLE END FLAP AT THE END OF EACH SIDEWALL PANEL, THE END FLAPS BEING JOINTED TO THE SIDEWALL PANELS ALONG A HORIZONTAL SCORE LINE AND THE TWO END FLAPS AT THE ENDS OF TWO ALTERNATE SIDEWALL PANELS HAVING SUBSTANTIALLY THE SAME LENGTH AS THE WIDTH OF EACH OTH THE OTHER TWO WALL PANELS, CUT LINES SEPARATING SAID END FLAPS AND TERMINATING SUBSTANTIALLY AT SAID HORIZONTAL SCORE LINE, DIVERGING SCORE LINES ON EACH ADJACENT PAIR OF WALL PANELS EXTENDING FROM A POINT ON THE VERTICAL SCORE LINE THEREBETWEEN TO THE HORIZONTAL SCORE LINE ON EITHER SIDE OF SAID VERTICAL SCORE LINE, COVERGING SCORE LINES ON THE END FLAPS AT THE ENDS OF SAID ADJACENT WALL PANELS EXTENDING FROM THE JUNCTIONS OF THE DIVERGING SCORE LINES WITH THE HORIZONTAL SCORE LINE TO THE CUT LINE BETWEEN SAID LAST NAMED END FLAPS AND BEING AT AN ANGLE OF 45* TO THE HORIZONTAL SCORE, LINE, AND DIAGONAL SCORE LINES AT THE OUTER CORNERS OF EACH OF SAID TWO END FLAPS EXTENDING FROM THE CUT LINES AT THE EDGES OF THE FLAPS TO THE ENDS OF THE FLAPS AT AN ANGLE OF 45* TO THE CUT LINES, SAID DIAGONAL SCORE LINES HAVING SUBSTANTIALLY THE SAME LENGTH AS SAID CONVERGING SCORE LINES. 